Setup Visual Studio Code with a debug config to run a Jest test. Select the test in an editor and run the debug task.

launch.json

{
    // Use IntelliSense to learn about possible Node.js debug attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "JEST Test",
            "type": "node",
            "request": "launch",
            "program": "${workspaceRoot}/node_modules/jest/bin/jest.js",
            "stopOnEntry": false,
            "args": ["--runInBand", "${file}"],
            "cwd": "${workspaceRoot}",
            "preLaunchTask": null,
            "runtimeExecutable": null,
            "runtimeArgs": [
                "--nolazy"
            ],
            "env": {
                "NODE_ENV": "development"
            },
            "externalConsole": false,
            "sourceMaps": false,
            "outDir": null
        }
    ]
}